How to Filter a Natural Clay Pond
- 1). Select the appropriate-sized stock tank based on the volume of your pond: A 70-gallon stock tank will filter a 2,000 to 3,000 gallon pond; a 100-gallon stock tank will filter a 3,000 to 4,500 gallon pond; and a 150-gallon stock tank will filter a 4,500 gallon pond.
- 2). Position your stock tank built-in drain-and-plug to the rear of your tank. Hand-tighten the drain-and-plug bulkhead fitting and seal it with Teflon tape. Because your filter will not require cleaning, this drain will rarely, if ever, be used.
- 3). Cut the ceiling grate to rest on the bottom ridge of the tank, cut a 1 3/4-inch hole in the center, and set it aside.
- 4). Place the closet flange on the top center flat face of the tank, and trace the inside hole and mark the mounting holes. Cut the hole and drill the mounting holes.
- 5). Cut a piece of the remaining ceiling grate slightly larger than the diameter of the hole, and place it on the underside of the closet flange.
- 6). Apply silicon to the flat underside of the closet flange. Lay the closet flange and the ceiling grate flush on the tank, aligning the tank hole to the flange hole, and mount with screws. Wipe off any excess silicon.
- 7). Cut three lengths of PVC pipe: one length equal to the vertical height of the tank with the T fitting attached to the bottom; two lengths equal to the horizontal length of the tank when fitted with the L fittings and attached to the T fitting.
- 8). Slide the ceiling grate over the vertical length, and attach the three L fittings. Turn the horizontal L fittings to face opposite directions, and align the vertical fitting with your pond pump hose.
- 9). Place the 1 1/4- to 1 1/2-inch threaded nipple reducer in the vertical length L fitting. Tighten the PVC and fittings by twisting. Do not glue the T and L fittings to the PVC pipe, to ensure easier adjustment.
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Place the finished assembly into the bottom of the tank. - 11
Loosely toss enough filter media to reach the lip of the tank overflow. Do not pack the filter media; it should be loose inside the tank. - 12
Attach your pump to the vertical L fitting by threading the 1 1/4-inch nipple into the reducer and attaching a sump pump hose. Position your filter to allow for the outflow of water from the closet flange into your pond. - 13
Allow the filter to fill with water.
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